Microsurgical clipping for coil-extruded recurrent aneurysms: Case series and technical pearls

Background: Endovascular coil embolization is widely used for the treatment of intracranial aneurysms, offering minimally invasive access and favorable early outcomes. However, long-term durability remains a concern, with recurrences arising from coil compaction, sac regrowth, or incomplete occlusion. In rare instances, these failures present with coil extrusion, a technically demanding scenario that significantly limits endovascular retreatment options. Methods: We report three adult female patients with recurrent intracranial aneurysms involving the anterior communicating artery, middle cerebral artery bifurcation, and distal azygos anterior cerebral artery, all with imaging-confirmed coil extrusion following prior endovascular therapy. Recurrence occurred at 6 months, 10 years, and nearly 20 years, illustrating early, late, and very-late treatment failure. All patients underwent microsurgical clipping performed using neuronavigation, continuous neurophysiological monitoring, indocyanine green videoangiography, and intraoperative Doppler ultrasonography. Operative strategy, technical nuances, and intraoperative decision-making are described. A focused literature review was conducted to contextualize management strategies for this rare presentation. Results: Complete microsurgical reconstruction and aneurysm obliteration were achieved in all patients without coil extraction, bypass, procedure-related neurological morbidity, or mortality. Postoperative imaging confirmed stable clip placement and exclusion of the aneurysm sac. Despite the presence of coil extrusion and dense adhesions, meticulous microsurgical dissection combined with modern intraoperative adjuncts enabled safe and effective clip application without the need for coil removal. Conclusion: Coil extrusion is an uncommon but complex manifestation of aneurysm recurrence that may occur even decades after initial endovascular treatment and can affect a range of anterior circulation locations. This case series underscores the importance of lifelong imaging surveillance and demonstrates that, in carefully selected patients, microsurgical clipping remains a safe and definitive salvage strategy when guided by refined technique and contemporary intraoperative technologies.